Remove dependency on ui::ScaleFactor from ui/gfx

ui/gfx/image/canvas_image_source.cc

Index: ui/gfx/image/canvas_image_source.cc
diff --git a/ui/gfx/image/canvas_image_source.cc b/ui/gfx/image/canvas_image_source.cc
index 747625ac60d2b8a2087915e6c4fdd058b6c003c2..b336b3118104f0a36c1d246f42d7bde7b0b379d2 100644
--- a/ui/gfx/image/canvas_image_source.cc
+++ b/ui/gfx/image/canvas_image_source.cc
@@ -6,7 +6,6 @@
 
 #include "base/logging.h"
 #include "ui/gfx/canvas.h"
-#include "ui/base/layout.h"
 
 namespace gfx {
 
@@ -18,9 +17,8 @@ CanvasImageSource::CanvasImageSource(const gfx::Size& size, bool is_opaque)
       is_opaque_(is_opaque) {
 }
 
-gfx::ImageSkiaRep CanvasImageSource::GetImageForScale(
-    ui::ScaleFactor scale_factor) {
-  gfx::Canvas canvas(size_, scale_factor, is_opaque_);
+gfx::ImageSkiaRep CanvasImageSource::GetImageForScale(float scale) {
+  gfx::Canvas canvas(size_, scale, is_opaque_);
   Draw(&canvas);
   return canvas.ExtractImageRep();
 }